is known that Marcus made a large number of inscriptions declaring his loyalty to the paranoid emperor Caracalla. In every other case apart from the milestone his name has been erased. Roman historian Guy de la Bédoyère has proposed that Marcus may have been subsequently arrested, convicted of treason and executed on Caracalla's orders as happened to the governor of Gallia Narbonensis that same year. Excavations and investigations 1732 – Location of milecastle identified by Horseley. 1858 – Horseley's location was confirmed by Henry MacLauchlan. 1867 – The milecastle was located and identified by Bruce. Pre 1931 – Investigations on the northern portion of the milecastle by Hepple showed it to be a short-axis milecastle with type I gateways. Three courses of stone (up to 0.8m in height) were discovered on the 3.3m wide north wall. The side walls were discovered to be 2.41m thick. 1931 – Excavations by Birley, Brewis and Simpson confirmed the narrow side walls and recorded the dimensions of the milecastle as east to west and north to south. The west half of the northern gateway was said to have been in good condition, with the liner of the pivothole being found and deposited in the Black Gate Museum. 14 July 1997 – The milecastle structure was designated a Scheduled Ancient Monument. 1999 – Milecastles Project studied it, 2 trenches excavated on the platform showed it was deeply buried in colluvium. Evidence for activity outside the walls existed with a gully and pit which probably dated to the Roman era. Inside the milecastle most deposits were post-Roman including probable remains of a post-medieval barn. 1999 – The Centre for Archaeology undertook an interim assessment of the milecastle. The investigation reported that a very clear, distinct terrace could be seen in the ground. Two trenches were dug in the area. The first was a 6m by 2m trench outside the milecastle which showed a linear gully and a shallow pit which were dated to the Roman period by a pottery sherd. The second trench was 8m long and 2m wide and crossed the west wall of the milecastle, it showed the structure to be buried beneath a deep layer of hillwash. Post-Roman walls were found to have been built within the milecastle, which were presumed to have been gone by the 19th century as they are not mentioned by earlier reports. Finds included pottery, charcoal, coal, slag,